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The chemical synthesis of cyclic peptides is a well-established area of research. This has been further expanded by development of bio-orthogonal reactions that enable access to peptides of greater structural complexity. One approach utilizes 1,3-dichloroacetone to selectively link free cysteine side-chains with an acetone-like bridge via an SN2 reaction. Here, we have used this reaction to dimerize cyclic peptide monomers to create novel bicyclic dimeric peptides. We investigated a range of reaction parameters to identify the optimal dimerization conditions for our model systems. One of the acetone-linked dimeric peptides was analyzed for proteolytic stability in human serum and was observed to still be fully intact after 48 h. This study provides valuable insights into the application of 1,3-dichloroacetone as a tool in the synthesis of complex, multicyclic peptides.

© Georg Thieme Verlag KG Stuttgart. New York. Greater functional knee valgus (FKV) is thought to contribute to a greater risk of sustaining overuse running injuries. The hip is commonly implicated in greater functional knee valgus, but no studies have investigated the effects of hip taping on running kinematics. The present study investigated whether or not hip taping altered hip and knee kinematics compared to sham and no taping in female runners demonstrating excessive functional knee valgus. Lower limb stance-phase kinematics were collected from 23 female runners using three-dimensional motion capture. Participants performed over ground running at 3.5 m/s and 5.0 m/s. Three taping conditions (no tape; sham tape; hip tape) were tested. Statistical inference was performed using Statistical Parametric Mapping Hotelling's paired t-tests, with post-hoc paired t-tests. Hip taping significantly decreased hip adduction and internal rotation angles throughout stance phase by up to 7°, compared to sham and no taping. Hip taping significantly increased knee adduction, internal rotation, flexion, and reduced peak knee flexion angles, compared to no tape. Hip taping reduced excessive hip motion by clinically meaningful magnitudes, and also benefited knee frontal and transverse plane kinematics at the slower running speed. Hip taping may provide an immediate solution in correcting FKV in running.

Objectives: Evaluate the acute effect of low-Dye, placebo and no tape on motor behaviour in individuals with plantar fasciitis (PF). Design: Prospective, experimental. Setting: Motion analysis laboratory. Participants: Ten participants with PF and ten matched controls. Main outcome measures: Hopping behaviour (lower-limb stiffness and ankle angle at peak loading) were evaluated during low-load sleigh hopping, during three taping conditions. Stiffness and ankle angle were determined using three-dimensional motion analysis. Pain during submaximal loading was assessed with a numeric pain rating scale. Results: The lower-limb stiffness response to therapeutic taping was modulated by the presence of PF (interaction, F = 4.48, p = 0.018). Matched controls demonstrated a significant increase in stiffness post application of low-Dye taping (p = 0.001), stiffness was unchanged in the PF group. In the PF group, low-Dye taping decreased hopping pain in comparison to placebo (p = 0.037) and no-tape (p = 0.024). There was no difference in ankle angle at peak loading between the groups or across taping conditions. Conclusions: Low-Dye taping reduces nociceptive inputs more than placebo in the presence of PF pain. Low-Dye tape alters stiffness in the control group but not the PF group. The motor behavioural outputs such as stiffness, during low-load hopping is modulated by both pathology and therapeutic taping.

© by the National Athletic Trainers' Association, Inc. Context: Because of the increasing popularity of participation in Irish dance, the incidence of lower limb injuries is high among this competitive population. Objective: To investigate the effects of fatigue on the peak lower limb and trunk angles as well as the peak lower limb joint forces and moments of competitive female Irish dancers during the performance of a dance-specific single-limb landing. Design: Cross-sectional study. Setting: Laboratory. Patients or Other Participants: Fourteen healthy, female, competitive Irish dancers (age = 19.4 ± 3.7 years, height = 165.3 ± 5.9 cm, mass = 57.9 ± 8.2 kg). Intervention(s): Participants performed an Irish dance-specific leap before and after a dance-specific fatigue protocol. During each landing movement, 3-dimensional lower limb kinematics (250 Hz) and ground reaction forces (1000 Hz) were collected. Paired t tests were performed to determine the differences (P ≤ .05) in lower limb and trunk biomechanics prefatigue and postfatigue. Main Outcome Measure(s): Peak lower limb and trunk angles as well as peak lower limb joint reaction forces and external moments. Results: Compared with the prefatigue trials, dancers landed with reduced ankle plantar flexion (P = .003) and hip external rotation (P = .007) and increased hip-adduction alignment (P = .034) postfatigue. Dancers displayed greater anterior shear (P = .003) and compressive (P = .024) forces at the ankle and greater external knee-flexion moments (P = .024) during the postfatigue compared with the prefatigue landing trials. Conclusions: When fatigued, dancers displayed a decline in landing performance in terms of aesthetics as well as increased ankle- and knee-joint loading, potentially exposing them to a greater risk of injuries.

© 2015 Sports Medicine Australia. Objectives: It has been reported that obtaining an adduction-to-abduction strength ratio of 90-100%, and an adduction strength equal to that of the uninjured side, are suitable clinical milestones for return to sport following groin injury. Little is known about hip adduction and abduction strength profiles in Australian footballers. This study aimed to compare isometric hip adduction and abduction strength profiles between preferred and non-preferred kicking legs in elite, sub-elite and amateur Australian footballers. Design: Cross sectional study. Methods: 36 elite, 19 sub-elite and 18 amateur Australian footballers, with a mean age of 24, 19 and 23 years respectively, were included. Maximal hip isometric adduction and abduction strength were measured using a hand held dynamometer with external belt fixation. Results: There were no significant differences in isometric hip adduction (p = 0.262) or abduction (p = 0.934) strength, or the adduction-to-abduction ratio (p = 0.163), between preferred and non-preferred kicking legs, regardless of playing level. Elite players had significantly greater isometric hip adduction and abduction strength than both sub-elite (mean difference; adduction = 46.01. N, p <. 0.001, abduction = 30.79. N, p = 0.003) and amateur players (mean difference; adduction = 78.72. N, p <. 0.001, abduction = 59.11. N, p <. 0.001). There was no significant difference in the adduction-to-abduction ratio between the playing levels (p = 0.165). Conclusions: No significant differences were found between preferred and non-preferred kicking legs across the playing levels for isometric hip adduction, abduction or the adduction-to-abduction ratio. This may have implications for developing groin injury prediction and return to sport criteria in Australian footballers.